SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'faa924c0b868d5b6edb4fb12d65ff295b54dccb86678f18656988715bccbc2de' 
  AND token = 'ovpL8mnMUoPQ1QFcnyvlvEXkXT+B+FRIcEnZLaGOWl8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}